DSD Information System
Home >> Toyota >> 2021 >> Highlander LE, 4WD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (2GR-FKS) - Diagnostic Codes (2 Of 6) >> SFI System >> DTC P0128-00: Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature); DTC P0128-07: Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature) Mechanical Failure [12/2019 - 10/2022] >> Monitor Strategy

Monitor Strategy

Related DTCs P0128: Coolant thermostat (judgment by simulated engine coolant temperature)
P0128: Coolant thermostat (judgment by engine coolant temperature change at high vehicle speed)
Required Sensors/Components (Main) Thermostat
Engine coolant temperature sensor
Required Sensors/Components (Related) Intake air temperature sensor (for mass air flow meter sub-assembly)
Vehicle speed sensor
Frequency of Operation Once per driving cycle: Judgment by simulated engine coolant temperature
Continuous: Judgment by engine coolant temperature change at high vehicle speed
Duration 306 seconds: Judgment by simulated engine coolant temperature
-: Judgment by engine coolant temperature change at high vehicle speed
MIL Operation 2 driving cycles
Sequence of Operation None